ESA scientists are currently testing intermetallic materials, combinations of metal similar to alloys in which two or more metals are diffused together on a molecular level. Titanium aluminide is an intermetal that could cut the weight of fan blades in jet engines by half. Unfortunately, titanium aluminide tends to fail under high temperatures. This can be solved by introducing small amounts of other materials, such as niobium. In Earth gravity, weight differences between the different metals makes it difficult to get them to diffuse properly.

Small-scale tests in rockets have shown that zero-g solves many of the issues with intermetallic production. The ESA will run larger tests over longer periods of time in the new Columbus science module on the ISS. These space metals could revolutionize the aerospace industry. Photo by: NASA.

'Space metals' aid perfection quest. [BBC]

The usual Scoville test involves diluting a sauce until taste testers can't detect heat anymore — the amount required to dilute it gives it a rating on the Scoville Scale. Chromatography can give you an accurate reading of capsaicinoids, but it's neither cheap nor easy. The new test uses carbon nanotube electrodes to draw in capsaicin molecules, which have a unique electrochemical response. When the capsaicinoids react, the device measures the current change and determines exactly how many were present. It can even translate this number into Scoville Units.

While the developers think this will be very useful in the food industry, where it can be deployed right on the production line, I've got a better idea. We can use it to develop a hot sauce so intense that we can cover our bodies with it to protect us from hungry robots. Image by: Viewoftheworld.

Chemists Measure Chilli Sauce Hotness With Nanotubes. [Science Daily]

Here you can see pictures taken by Tony Travouillon of giant chunks of ice in Antarctica that have been sculpted by the wind to look like huge waves erupting out of the ground.

You can see more beautiful ice bubbles here and here.

Cranberry Lake photo via BLDGBLOG and New Scientist. Antarctic wave via Travouillon's website.

At the Astrobiology Science Conference 2008 that wrapped up yesterday, chemist Steve Benner proposed that formamide might make a great solvent for life with some bizarre biochemistry that mimics our DNA, but in a way we can only imagine. Benner's a great speaker and scientist, but has a tendency to lapse into flights of chemical minutia, so I'll take a page from a New Scientist feature in June that aptly sums up the point:

A suitable solvent is only part of the story of life, of course. Apart from a few viruses, all life on Earth uses deoxyribonucleic acids (DNA) to encode the information needed to build and run an organism. But is there an alternative? Could genetic information be stored another way?

DNA consists of a double helix, like a twisted ladder. Every rung of the ladder comprises a pair of molecules called bases. These bases are the part of DNA that actually encode the genes. There are four types, known by the initials G, A, C and T, and they form the alphabet of every genetic code. The struts of the ladder consist of deoxyribose sugars linked by charged phosphate groups.

Biologists have methodically altered different parts of the DNA molecule to explore which aspects of its structure are necessary for it to function properly. They have identified several parts that can be changed without disrupting the molecule. For example, you can replace deoxyribose with another sugar, such as threose. Different and more molecules can be used to represent the bases too.
DNA disaster

But that's where the known options end, says Steven Benner, a synthetic biologist at the Foundation for Applied Molecular Evolution in Gainesville, Florida. Benner has found that replacing the phosphate groups with uncharged substitutes brings disaster. The DNA strand becomes unstable, collapses into a ball and sinks to the bottom of his experimental solution like dregs in a beer keg.

Before these experiments, people wondered why the phosphates were there - whether they were simply a redundant evolutionary artefact, rather like a male nipple. It's now clear that they serve a vital function. The charges keep DNA stiff by organising a cradle of water molecules along its chain; without them, DNA easily wads into a ball - another demonstration of how water is integral to life as we know it. An alien's DNA equivalent in ammonia or methane, say, would therefore need some very different structures to avoid rolling up. Those charged phosphates might have to be replaced by something greasier, like hydrocarbon or benzene molecules, says Jack Szostak, a molecular biologist at Harvard University.

Source: original reporting, New Scientist (sub required)

Image: ufocasebook.com

In March 2006, researcher Stefan Kruszewski wrote in The American Journal of Psychiatry:

Modanifil is reinforcing, as evidenced by its self-administration in monkeys previously trained to self-administer cocaine.

Modafinil and cocaine dose-dependently increased heart rate and blood pressure. The results of the present study suggest that modafinil has minimal abuse potential, but should be viewed cautiously because of the relatively small sample size. Future studies should further characterize the abuse potential of modafinil using other behavioral arrangements, such as drug discrimination or drug self-administration. A full characterization of the abuse potential of modafinil will become important as the use of this drug increases.

In early trials, several candidate medications—bupropion, modafinil, and, to a lesser extent, baclofen—have shown promise in treating aspects of methamphetamine dependence, including aiding memory function necessary to more effectively participate in and benefit from behavioral therapies.

According to an early release about her scientific paper:

Scientists have long known that most compounds in living things exist in mirror-image forms. The two forms are like hands; one is a mirror reflection of the other. They are different, cannot be superimposed, yet identical in their parts.

When scientists synthesize these molecules in the laboratory, half of a sample turns out to be "left-handed" and the other half "right-handed." But amino acids, which are the building blocks of terrestrial proteins, are all "left-handed," while the sugars of DNA and RNA are "right-handed." The mystery as to why this is the case, "parallels in many of its queries those that surround the origin of life," said Pizzarello.

Years ago Pizzarello and ASU professor emeritus John Cronin analyzed amino acids from the Murchison meteorite (which landed in Australia in 1969) that were unknown on Earth, hence solving the problem of any contamination. They discovered a preponderance of "left-handed" amino acids over their "right-handed" form.

"The findings of Cronin and Pizzarello are probably the first demonstration that there may be natural processes in the cosmos that generate a preferred amino acid handedness," Jeffrey Bada of the Scripps Institution of Oceanography, La Jolla, Calif., said at the time.

The new PNAS work was made possible by the finding in Antarctica of an exceptionally pristine meteorite. Antarctic ices are good "curators" of meteorites. After a meteorite falls — and meteorites have been falling throughout the history of Earth — it is quickly covered by snow and buried in the ice. Because these ices are in constant motion, when they come to a mountain, they will flow over the hill and bring meteorites to the surface.

"Thanks to the pristine nature of this meteorite, we were able to demonstrate that other extraterrestrial amino acids carry the left-handed excesses in meteorites and, above all, that these excesses appear to signify that their precursor molecules, the aldehydes, also carried such excesses," Pizzarello said. "In other words, a molecular trait that defines life seems to have broader distribution as well as a long cosmic lineage."

ASU Researcher May Have Discovered Key to Life Before Its Origin on Earth [Eurekalert]

The machine analyzes the gas espresso gives off when heated, translating combinations of ions into subjective descriptions like "roasted, flowery, woody, toffee and acidity." Called an "electronic taster," it was created by chemical engineers at Nestle in Switzerland, and will be used as a quality control device in the coffee industry. And perhaps as an evaluation tool for a few coffee snobs (for the record, the machine only tastes ristretto pulls).

Analytical Chemistry published an article this week about the amazing machine, including a precise scientific evaluation of "coffee headspace." According to a release about the research:

The multisensory experience from drinking a cup of coffee makes it a particular challenge for flavor scientists trying to replicate these sensations on a machine. More than 1,000 substances may contribute to the complex aroma of coffee.

Coffee scientists have long been searching for instrumental approaches to complement and eventually replace human sensory profiling.

When Machine Tastes Coffee [Analytical Chemistry]